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United States Patent |
6,133,337
|
Blum
,   et al.
|
October 17, 2000
|
Use of reactive prepolymeric organic compounds
Abstract
The invention relates to the use of reactive prepolymeric organic
compounds, containing structural units having at least one readily
abstractable hydrogen with a bond energy of not more than 397 kJ/-mol and
having at least one ethylenic double bond, for crosslinking, with or
without free-radical initiators, by means of heat, high-energy radiation
or heat and high-energy radiation.
Inventors:
|
Blum; Rainer (Ludwigshafen, DE);
Loerzer; Thomas (Landau, DE);
Hegemann; Gunther (Hamburg, DE);
Baumgarten; Gunther (Hamburg, DE)
|
Assignee:
|
BASF Aktiengesellschaft (Ludwigshafen, DE)
|
Appl. No.:
|
101243 |
Filed:
|
September 30, 1998 |
PCT Filed:
|
December 20, 1996
|
PCT NO:
|
PCT/EP96/05769
|
371 Date:
|
September 30, 1998
|
102(e) Date:
|
September 30, 1998
|
PCT PUB.NO.:
|
WO97/25361 |
PCT PUB. Date:
|
July 17, 1997 |
Foreign Application Priority Data
| Jan 04, 1996[DE] | 196 00 146 |
Current U.S. Class: |
522/104; 522/90; 522/91; 522/96; 522/108; 523/500; 526/346 |
Intern'l Class: |
C08F 002/46; C08F 002/48 |
Field of Search: |
522/96,90,91,104,108
523/500
526/346
|
References Cited
U.S. Patent Documents
4801629 | Jan., 1989 | Stavinoha et al. | 523/500.
|
5319006 | Jun., 1994 | Yang et al. | 523/500.
|
5620751 | Apr., 1997 | Brindoepke et al. | 427/506.
|
Foreign Patent Documents |
101585 | Feb., 1984 | EP.
| |
118786 | Sep., 1984 | EP.
| |
166449 | ., 1986 | EP.
| |
166449 | Feb., 1986 | EP.
| |
186165 | Feb., 1986 | EP.
| |
260688 | Mar., 1988 | EP.
| |
302484 | Feb., 1989 | EP.
| |
430906 | May., 1991 | EP.
| |
585742 | Mar., 1994 | EP.
| |
684284 | Nov., 1995 | EP.
| |
1570323 | Feb., 1970 | DE.
| |
3107450 | Oct., 1982 | DE.
| |
1057727 | Feb., 1967 | GB.
| |
Primary Examiner: Seidleck; James J.
Assistant Examiner: McClendon; Sanza
Attorney, Agent or Firm: Keil & Weinkauf
Claims
We claim:
1. A process for the preparation of crosslinked polymeric organic compounds
by crosslinking, with or without free-radical forming initiators, by means
of heat and/or high-energy radiation, in the absence of ethylenically
unsaturated monomeric reactive diluents, at least one first prepolymer
containing structural units having at least one ethylenic double bond and
a softening range of less than 130.degree. C., wherein either said first
prepolymer also contains structural units having at least one readily
abstractable hydrogen with a bond energy of not more than 397 kJ/mol,
wherein the readily abstractable hydrogens are incorporated into the
prepolymer by way of structures of the formula (I), (II), (III), (IV),
(V), (VIII), (IX),
##STR12##
where --R-- is oxygen or a divalent radical having one or more ester,
amide, urethane and/or ketone groups or is an ionic bond,
##STR13##
or by way of esters of isoprenol, or wherein said at least one first
prepolymer is mixed with at least one second prepolymer containing said
structural units having at least one readily abstractable hydrogen.
2. A process as claimed in claim 1, wherein polymeric organic compounds are
selected for crosslinking which contain structural units having at least
one ethylenic double bond and structural units having at least one readily
abstractable hydrogen with a bond energy of not more than 397 kJ/mol in
the same molecule.
3. A process as claimed in claim 1, wherein the readily abstractable
hydrogens are .alpha. to a double bond (allylic hydrogens).
4. A process as claimed in claim 1, wherein the readily abstractable
hydrogens are incorporated by way of structures of the formula (V)
##STR14##
or by way of esters of isoprenol.
5. A process as claimed in claim 1, wherein the readily abstractable
hydrogens are incorporated by way of structures of the formula (VIII)
and/or (IX)
##STR15##
6. A process as claimed in claim 2, wherein said prepolymers are
unsaturated polyester resins based on .alpha.,.beta.-olefinically
unsaturated dicarboxylic acids into which at least one of the groups
containing readily abstractable hydrogens, of the formulae (I), (II),
(III), (IV), (V), (VII) and (IX), or a group resulting from an isoprenol
ester, has been incorporated.
7. A process as claimed in claim 1, wherein the crosslinked polymeric
organic compounds are formed from mixtures of unsaturated polyester resins
which are based on .alpha.,.beta.-olefinically unsaturated dicarboxylic
acids and are devoid of groups having readily abstractable hydrogens, and
prepolymers containing groups having readily abstractable hydrogens.
8. A process as claimed in claim 1. wherein said first or second, or both
first and second, prepolymers are derived from monofunctional alcohols,
polyfunctional alcohols, alkoxylation products thereof, polyether polyols,
polyester polyols, polytetrahydrofuran and/or polycaprolactone, which at
the ends contain structural components which are attached by way of esters
of .alpha.,.beta.-olefinically unsaturated dicarboxylic acids and which
have readily abstractable hydrogens.
9. A process as claimed in claim 1, wherein either or both of said
prepolymers include customary free-radical initiators, C-C-labile
substances and reaction accelerators, stabilizers and further additives
from the group consisting of viscosity regulators, flow improvers and
gloss enhancers.
10. A process as claimed in claim 1, wherein cross linking is carried out
using one or more crosslinking agents, selected from polyfunctional
isocyanates, amino resins and polyfunctional epoxides.
Description
The present invention relates to the use of reactive prepolymeric organic
compounds for crosslinking, with or without free-radical initiators, by
means of heat, high-energy radiation or heat and high-energy radiation.
Substances of this kind can be reacted, ie. polymerized further or
cross-linked, using high-energy radiation, preferably UV light, or by
means of free radicals at room temperature, using known combinations of
peroxides and co-initiators, for example heavy metal salts, or by means of
heat, using thermal free-radical initiators such as peroxides, azo
initiators or C-C-labile compounds. These methods of initiating reaction
can also be used in any desired combination, with possibilities including
both the combined use of thermally generated free radicals with
UV-generated free radicals and reaction to a B-stage, ie. a partially
reacted state at which the reaction is terminated and can be reinitiated
at a later point in time.
These reactive prepolymers may find application as paint binders, as
coating compositions, for the preparation of compact or cellular,
reinforced or nonreinforced molding compounds, casting compositions,
electrical-insulation compositions, daylight-curable roadmarking paints,
sealants and coating compositions, or as printing ink binders, binders for
nonwovens, adhesives, prepregs, etc.
Unsaturated polyester resins containing dihydrodicyclopentadiene (DHCPD)
structural units, which resins are generally used dissolved in monomeric
reactive diluents such as styrene, .alpha.-methylstyrene, vinyltoluene,
allyl phthalate, acrylates, vinylates or the like, are the subject of
numerous patents. The use of these reactive diluents, which in the case
of, for example, powder coatings may also be solid substances, is regarded
in the prior art as being essential, owing to the inadequate
homopolymerizability of the maleic and fumaric acid double bonds.
DE 31 07 450 relates to unsaturated polyesters which have oligomers of
cyclopentadiene as end groups and can be used, as solutions in
ethylenically unsaturated monomers, for preparing moldings and coatings;
the use thereof without reactive diluents, however, cannot be derived from
this document.
EP 101 585-A relates to unsaturated polyester resins which are modified by
the addition of cyclopentadiene onto the double bond of the polyester and
are then dissolved in vinyl monomers.
EP 118 786-A describes unsaturated polyester resins which are modified with
dicyclopentadiene and, dissolved in vinyl or allyl monomers, are cured in
a two-stage process to give molding compounds offering high temperature
stability.
EP 260 688-A also relates to polyester resins, which are dissolved in
vinylic monomers.
DE 32 30 924-A describes a special process for preparing polyester resins
which contain cyclopentadiene structures and are dissolved in vinyl
monomers.
EP 585 74 2-A relates to mixtures of solid substances containing
unsaturated polyester resins and polyurethane acrylate resins. These
mixtures are suitable as powder coatings which, after being melted, are
crosslinked under UV light in the presence of UV initiators.
EP 0 684 284-A1 describes synergistic mixtures of unsaturated polyether
ester resins and dicyclopentadiene polyester resins, which are dissolved
in styrene and are cured in the presence of peroxidic catalysts.
DE-A-15 702 73 describes polyesters whose ends carry 5- or 6-membered imide
rings, derived for example from tetrahydro-phthalimidoethanol, and are
dissolved in unsaturated monomers.
The present invention provides for the use of reactive prepolymeric organic
compounds, containing structural units having at least one readily
abstractable hydrogen with a bond energy of not more than 397 kJ/mol and
having at least one ethylenic double bond, for crosslinking, with or
without free--radical initiators, by means of heat, high-energy radiation
or heat and high-energy radiation.
Preferred such compounds are those whose readily abstractable hydrogens are
a to a double bond (allylic hydrogens), and especially those whose readily
abstractable hydrogens have been incorporated into the prepolymers by way
of structures of the formulae (I), (II), (III) and/or (IV),
##STR1##
where --R-- is oxygen or a divalent radical having one or more ester,
amide, urethane and/or ketone groups or is a salt-type bond, or are
incorporated by way of structures of the formulae (V), (VI), (VII),
(VIII), (IX) and/or (X) or by way of esters of isoprenol (Va)
##STR2##
where n=1 to 20,
##STR3##
The reactive prepolymeric organic compounds to be used in accordance with
the invention can be unsaturated polyester resins based on
.alpha.,.beta.-olefinically unsaturated dicarboxylic acids and into which
at least one of the groups containing readily abstractable hydrogens, of
the formulae (I) to (X), has been incorporated, or are mixtures of
unsaturated polyester resins which are based on
.alpha.,.beta.-olefinically unsaturated dicarboxylic acids and are devoid
of groups having readily abstractable hydrogens and prepolymeric organic
compounds containing groups having readily abstractable hydrogens.
These prepolymeric organic compounds may also be derived from
monofunctional alcohols, polyfunctional alcohols, alkoxylation products
thereof, polyetherpolyols, polyesterpolyols, polytetrahydrofuran and/or
polycaprolactone, which at the ends contain structural units which are
attached by way of esters of .alpha.,.beta.-olefinically unsaturated
dicarboxylic acids and which have readily abstractable hydrogens.
Particular preference is given to the use of reactive prepolymeric organic
compounds which are liquid at room temperature or have softening ranges in
accordance with DIN 53180 of less than 130.degree. C. at a viscosity of
below 100,000 mPas at 100.degree. C. and at the same time are stable in
terms of viscosity for at least 24 hours at a temperature at which they
have a viscosity of not more than 10,000 mPas, and are melted or heated in
the course of processing.
The reactive prepolymeric substances to be used in accordance with the
invention can be employed, alone or together with other binders and/or
organic and/or inorganic fillers, as paint binders, as coating
compositions, for the preparation of compact or cellular, reinforced or
nonreinforced molding compounds, casting compositions,
electrical-insulation compositions for electrical windings, wire enamels
for insulating winding wires in electrical engineering, daylight-curable
roadmarking paints, sealants and coating compositions, or as printing ink
binders, as adhesives or as binders for ordered and random-laid, planar or
any shaped fiber support materials made from organic or inorganic
substances.
The reactive prepolymeric organic compounds to be used in accordance with
the invention can be employed together with customary free-radical
initiators, C-C-labile substances and reaction accelerators, with
stabilizers and with further additives from the group consisting of
viscosity regulators, flow improvers and gloss enhancers.
Furthermore, the reactive prepolymeric organic compounds to be used in
accordance with the invention can, for curing, be employed together with
one or more curing mechanisms, known per se, selected from cocrosslinking
with polyfunctional isocyanates, amino resins and polyfunctional epoxides.
The reactive prepolymeric organic compounds to be used in accordance with
the invention contain structural units having at least one readily
abstractable hydrogen with a bond energy of not more than 397 kJ/mol and
having at least one ethylenic double bond.
Data on bond energy are given in the literature and can be taken, for
example, from Morrison, Robert Thornton, Organic Chemistry (Table:
Homolytic Bond Dissociation Energies, on the inside cover) in Library of
Congress Cataloging-in-Publication Data ISBN-205-08453-2 (1987) by Allyn
and Bacon, Inc., A Division of Simon & Schuster, Newton, Mass., U.S.A.
These reactants may be present in the same molecule. The reactive
prepolymeric substances (organic compounds) may also, however, consist of
mixtures of prepolymers containing only the readily abstractable hydrogens
with prepolymers containing only the ethylenic double bonds. It is also
possible in the course of curing to employ one or more known curing
mechanisms, for example cocrosslinking with polyfunctional isocyanates,
amino resins, such as melamine-, urea- or benzoguanamine-formaldehyde
resins, polyfunctional epoxides, etc. The additionally employable
crosslinking mechanisms may also lead to formation of interpenetrating
networks in the coatings, by means of which specific, desirable
properties, eg. particularly high chemical resistance, are often achieved.
The novel structural units having at least one readily abstractable
hydrogen with a bond energy of not more than 397 kJ/mol are incorporated,
for example, by way of structures of the formulae (I) to (IV) derived from
dihydrodicyclopentadiene
##STR4##
where --R-- is oxygen or a divalent radical having one or more ester,
amide, urethane and/or ketone groups or is a salt-type bond.
Examples of other structures which can be incorporated into the novel
substances by way of the readily abstractable hydrogens are radicals from
the group consisting of isoalkyls, aminoisoalkyls, cycloisoalkyls,
cycloisoalkyls having one or more heteroatoms, isoalkylaryls, or
structures of the formulae below, where
n=2 or 3,
R.sup.2 is a bivalent aliphatic or aromatic radical of, for example, up to
8 carbons, or is a single bond,
R.sup.3 is a bivalent aliphatic, cycloaliphatic, heterocyclic or aromatic
radical, substituted or unsubstituted, or is a single bond,
R.sup.4 is H, straight-chain or branched alkyl of, for example, 1-8
carbons, halosubstituted aryl or isoamylphenyl,
R.sup.5 is alkyl, halosubstituted alkyl, halosubstituted aryl or
isoamylphenyl,
for example
##STR5##
The reactive prepolymeric organic compounds to be used in accordance with
the invention can be either linear or contain one or more branching sites
and possess, for example, the structures reproduced by formulae (XI) and
(XII), where --R-- is a bridging group or a single bond and D-- is a
structure having readily abstractable hydrogens. In this context the
ethylenic double bonds can be both in the radicals --R-- and at other
sites in the molecule or in any prepolymeric substances devoid of D--
which are mixed with prepolymeric substances containing D--. The
structures reproduced by formulae (XI) and (XII) are intended merely to
illustrate the principle by way of example.
##STR6##
Substances accessible with particular ease are those in which --R-- is an
ester group, and can be obtained by addition of dicyclopentadiene (DCPD)
onto polyfunctional polycarboxylic acids, in which reaction the use of
catalysts such as boron trifluoride etherate may be necessary for a high
conversion. Adducts which are very easy to obtain are those of maleic
anhydride and water with DCPD, of formulae (XIII) and (XIV).
In the case of adducts of the formulae (XIII) and (XIV) and novel reactive
prepolymeric substances based on these, no distinction is made between the
isomers fumaric acid and maleic acid; depending on the reaction
conditions, different proportions of the isomers are formed. Any mixtures
are within the scope of the present invention.
##STR7##
Using these substances it is easy to obtain, by reaction with
carboxyl-reactive polymers, the substances to be used in accordance with
the invention. Examples of such polymers are mono- and polyfunctional
hydroxy compounds, carboxylic esters of mono- and polyfunctional polymeric
hydroxy compounds, mono- and polyfunctional polymeric epoxides,
hydroxy-functional natural oils and resins, epoxidized natural oils and
resins, mono- and polyfunctional polymeric isocyanates, and mono- and
polyfunctional polymeric amines.
Dihydrodicyclopentadienol of the formula (XV) and isoprenol of the formula
(Va) are commercially available and can be used to synthesize the novel
substances by reaction with OH reactive substances.
##STR8##
Furthermore, groups containing allylic hydrogens can be introduced by way
of the imides of cyclic unsaturated dicarboxylic acids with
aminocarboxylic acids or amino alcohols. Examples are shown by the
formulae (XVI) and (XVII). Other substances having readily abstractable
hydrogens and OH groups are endomethylenetetrahydrophthalic acid and
derivatives thereof, such as methylendomethylenetetrahydrophthalic acid or
endomethylenetetrahydrophthalimidols of the formula (XVI)
##STR9##
and tetrahydrophthalic acid and its derivatives, such as
methyltetrahydrophthalic acid and tetrahydrophthalimidols of the formula
(XVII)
##STR10##
These compounds are suitable for synthesizing the novel substances, by
reaction with OH reactive substances.
Where the substances to be used in accordance with the invention contain
double bonds in the polymer chain, for example as maleic or fumaric or
itaconic esters, then grafting with cyclopentadiene produces
endomethylenetetrahydrophthaloyl structures of the formula (XVIII), which
also contain readily abstractable hydrogens.
##STR11##
Furthermore, derivatives of cyclic dicarboxylic acids containing allylic
hydrogen are obtained by Diels-Alder reaction of maleic acid-containing
polyesters with other dienes, such as butadiene or pentadiene.
An important class of substances to be employed in accordance with the
invention comprises the esters of substances of the formulae (XIII) and
(XIV) and of the maleic and fumaric monoesters of isoprenol with
alkoxylated mono- and polyols, each of which esters may include 2-2000
ethylene oxide and/or propylene oxide units per molecule, examples being
ethoxylated or propoxylated trimethylolpropane, ethoxylated or
propoxylated pentaerythritol, ethoxylated or propoxylated glycerol,
polyethylene glycol monoalkyl ethers, polypropylene glycol monoalkyl
ethers, polyester- and polyetherpolyols of the polyethylene oxide,
polypropylene oxide, polytetrahydrofuran and polycaprolactone type. The
introduction of molecular pseudo-plasticity and improved elasticity for
the cured substances is achieved by incorporating long-chain polyethylene
terephthalate units or polybutadienediol. Also suitable are esters of the
abovementioned hydroxy compounds with the mono-esters of alcohols having
readily abstractable hydrogens, for example furfuryl alcohol,
tetrahydrofurfuryl alcohol, 1-alkylalkenols or substances of the formulae
(XVI) and (XVII) with dicarboxylic acids, for example maleic acid, fumaric
acid, itaconic acid, citraconic acid, phthalic acid and isomers thereof.
By the type of alkoxylating agent and the degree of alkoxylation it is
possible in such novel substances to control, as well, properties of the
end products, such as, for example, hardness, hydrophilicity and
elasticity. It is possible in this context for the polyols to be only
partially esterified, with the remaining hydroxyls either being left free,
esterified or etherified with other substances which may or may not
contain readily abstractable hydrogens, or reacted with other reactive
substances. Examples of compounds suitable for this purpose are
isocyanates or epoxides. Also of importance are hydroxyl- containing
natural oils such as castor oil, for example. Another important class of
substances comprises unsaturated polyester resins based on
.alpha.,.beta.-unsaturated carboxylic acids such as maleic acid, fumaric
acid, itaconic acid and/or citraconic acid containing structural units
having readily abstractable hydrogens. As already mentioned above,
unsaturated polyester resins containing DCPD structural units, which are
used as solutions in monomeric reactive diluents such as styrene,
.alpha.-methylstyrene, vinyltoluene, allyl phthalate, acrylates and
vinylates or the like, are the subject of numerous patents. The use of
these reactive diluents, which in the case of powder coatings, for
example, may also be solid substances, is considered in the prior art to
be essential owing to the inadequate homopolymerizability of the maleic or
fumaric acid double bonds.
Unsaturated polyester resins for the purposes of the present invention are
polyesters, known per se, which include structural units having readily
abstractable hydrogens. The polyesters to be used in accordance with the
invention are synthesized by known, prior art polyester preparation
techniques, generally by polycondensation of polyfunctional hydroxy
compounds with polyfunctional acids and/or their anhydrides at elevated
temperatures. In addition, it is often advantageous to start from the
esters of such substances, and to produce the polyesters by
transesterification at elevated temperatures, since transesterification
reactions of this kind in some cases proceed more readily and more rapidly
than the direct esterification. It is also possible, by using (in part or
in toto) polyfunctional amines, to obtain binders having amide structures.
The partial use of monofunctional starting materials is also possible in
order, for example, to regulate the molecular weight. The starting
materials listed in the text below should be regarded merely as examples
for illustrating the invention.
Examples of suitable starting materials are: di- and polycarboxylic acids,
such as adipic acid, suberic acid, phthalic acid isomers,
tetrahydrophthalic acid, endomethylene-tetrahydrophthalic acid,
hexahydrophthalic acid, fumaric acid, maleic acid, itaconic acid,
citraconic acid, trimellitic acid, pyromellitic acid, di- and polyols,
such as ethylene glycol, polyethylene glycols, propylene glycol,
polypropylene glycols, butanediol isomers, hexanediol, neopentylglycol,
trimethylolpropane, glycerol, pentaerythritol, bisphenol A, hydrogenated
bisphenol A, OH-polyfunctional polymers, such as hydroxyl-modified
polybutadienes or hydroxyl-carrying polyurethane prepolymers and epoxy
resins, polyfunctional natural substances or derivatives thereof, such as
linseed oil fatty acid. Also of importance are alkoxylated OH-functional
substances, examples being the ethoxylation and propoxylation products of
the abovementioned polyols.
The introduction of amide and imide structures is also known prior art in
accordance with DE-A-15 70 323. Such polyester amides or polyester imides
are able to meet certain requirements, for example in respect of thermal
stability, in many cases better than pure polyesters. The synthesis of the
polyesters within the scope of the present invention, with specific
requirements relating, for example, to hardness, elasticity, viscosity
and/or softening point, is done in accordance with rules known to the
skilled worker. For example, the skilled worker is aware of how to vary
the elasticity of cured polyester resins by the chain length of the
polyols or polycarboxylic acids. For example, polyester resins synthesized
using hexanediol or adipic acid are more flexible than those based on
phthalic acid and ethylene glycol. Furthermore, the control of the
properties by the additional use of polyfunctional substances, which
produce branching in the polyester molecules, such as trimellitic acid or
trimethylolpropane, is known to the skilled worker. In this context, the
introduction of structural components having readily abstractable
hydrogens into the polyesters can be carried out, for example, by the
additional use of cocondensable starting materials which carry readily
abstractable hydrogens. Readily and inexpensively obtainable starting
materials of this kind are the adducts of maleic anhydride and water with
DCPD, of formulae (XIII) and (XIV), which can be used along with other
compounds to synthesize the polyesters.
Furthermore, it is also possible to use dihydrodicyclopentadienol of
formula (XV) in the synthesis of the polyesters, thereby likewise
introducing structures having readily abstractable hydrogens.
Examples of other substances for synthesizing polyesters containing
structural components having readily abstractable hydrogens are
1-methylalkenols, tetrahydrophthaloylaminoalkanols of formula (XVI),
endomethylenetetrahydrophthaloylaminoalkanols of formula (XVII),
isoprenol, furfurol and tetrahydrofurfurol.
The majority of unsaturated polyesters are very highly viscous or solid
resins. A particular feature of the present invention is the use of novel
substances of the formulae (XI) and (XII), which are not customary
polyester resins and in some cases are low-viscosity liquids with a very
high boiling point; as a result, they represent reactive diluents which
are specifically adapted to the novel systems and are devoid of the
disadvantages of the known, monomeric reactive diluents, containing
acrylic or vinylic unsaturation, such as styrene or monomeric acrylates.
These substances carry two or more of the reactive groups having readily
abstractable hydrogens, or contain these groups in high molar
concentration, in the case of monoesters of lower alcohols or diols with
substances of the formulae (XIII) and (XIV). They are therefore highly
reactive crosslinking agents which in many cases can be used alone but are
preferably present along with other substances in customary linear
polyester resins or those with low degrees of branching.
It is therefore possible to establish the softening range or viscosity
range important for application without generating higher emissions in the
course of processing and curing. Thus, polyesters of relatively high melt
viscosity and high softening point can be used for the present invention
and the desired, low processing viscosity can be established by adding
these substances. It is also possible to use, in part, polyesters already
known per se. The reactivity of the substances with themselves, and
especially the novel reactive mixtures of unsaturated polyester resins
with polyfunctional substances which are not polyesters, and correspond to
the formulae (XIII) and (XIV), for crosslinking, without the partial use
of monomeric or polymeric reactive diluents, are novel.
Following the addition of substances which form free radicals on heating,
the reactive prepolymeric substances to be used in accordance with the
invention are able to cure thermally. Examples of known free-radical
initiators are peroxides, azo compounds, azides and C-C-labile substances.
A considerable acceleration in curing, or reduction in curing temperature,
can be achieved with metal coinitiators, for example compounds of cobalt,
manganese, iron, nickel or lead.
Furthermore, in the presence of UV initiators of the .alpha.-cleaving type
(Norrish type I) or of the H-donor/acceptor system type (Norrish type II),
the novel polymers are of high UV sensitivity.
It is also possible to produce substances to be used in accordance with the
invention and which have enhanced photosensitivity as a result of the fact
that their molecule carries H-acceptor groups, which can, for example,
beincorporated by way of hydroxy-functional phenone compounds such as
hydroxybenzophenone or bishydroxybenzophenone, for example.
The substances to be used in accordance with the invention, alone or
together with other binders and/or organic and/or inorganic fillers, can
be employed as paint binders, as coating compositions, for the preparation
of compact or cellular, reinforced or nonreinforced molding compounds,
casting compositions, electrical-insulation compositions, daylight-curable
roadmarking paints, sealants and coating compositions, or as printing ink
binders, adhesives, as binders for ordered and random-laid, planar or
formed fiber support materials made from organic or inorganic materials.
The novel substances are, in general, liquid and can be used directly. If
they are of too high a viscosity for processing or are solid, they can
also be heated, melted or used as a solution in solvents or dispersed in
water.
EXAMPLE 1
______________________________________
661.10 g Dicyclopentadiene
(5.0 mol) and
490.30 g maleic anhydride (5.0 mol)
______________________________________
were weighed into a stirring flask fitted with heater and distillation
device.
The mixture was then heated to 125.degree. C. under a gentle stream of
nitrogen, and then
______________________________________
95.00 g water (5.0 mol + 5 g)
______________________________________
were added from a dropping funnel over the course of one hour. The mixture
was left to after-react at 125.degree. C. for one hour. A monocarboxylic
acid of the formula (XIII) was formed which contains readily abstractable
hydrogens. The contents of the flask were cooled to 70.degree. C., and
then
______________________________________
1730.00 g ethoxylation product of trimethylolpropane
and ethylene oxide having an OH number of 165,
4.00 g dibutyltin dilaurate and
4.00 g hydroquinone
______________________________________
were added.
The mixture was then heated rapidly to 120.degree. C. under a gentle stream
of nitrogen. Subsequently, over the course of 6 hours, the temperature was
raised gradually to 190.degree. C. and the water of condensation produced
was removed by distillation, to give a highly viscous liquid having an
acid number of 18.
EXAMPLE 2
______________________________________
490.80 g maleic anhydride (5.0 mol)
______________________________________
were weighed into a stirring flask fitted with heater and distillation
device and were heated to 100.degree. C. under a gentle stream of
nitrogen, and then
______________________________________
444.80 g isoprenol (5.1 mol)
(2-methyl-but-1-ene-4-ol)
______________________________________
were added from a dropping funnel over the course of one hour. A slightly
exothermic reaction took place. The mixture was then left to after-react
at 125.degree. C. for one hour. A monoester of maleic/fumaric acid with
isoprenol was formed, which has readily abstractable hydrogens. The
contents of the flask were cooled to 70.degree. C., and then
______________________________________
1730.00 g ethoxylation product of trimethylolpropane and
ethylene oxide having an OH number of 165,
4.00 g dibutyltin dilaurate and
4.00 g hydroquinone
______________________________________
were added. The mixture was heated rapidly to 120.degree. C. under a gentle
stream of nitrogen. Subsequently, over the course of 6 hours, the
temperature was raised gradually to 190.degree. C. and the water of
condensation produced was removed by distillation, to give a highly
viscous liquid having an acid number of 26.
EXAMPLE 3
______________________________________
490.30 g maleic anhydride (5.0 mol) and
913.10 g tetrahydrophthaloylaminoethanol (5.1 mol)
(substance of formula (XVII) where R = --C.sub.2 H.sub.4 --)
______________________________________
were weighed into a stirring flask fitted with heater and distillation
device. The contents of the flask were heated under a gentle stream of
nitrogen and melted above about 70.degree. C., and an exothermic reaction
developed. After the reaction had subsided, heating was continued at
125.degree. C. for one hour. A monoester of maleic/fumaric acid with
tetrahydrophthaloylaminoethanol was formed, which contains readily
abstractable hydrogens.
The contents of the flask were cooled to 70.degree. C., and then
______________________________________
1730.00 g ethoxylation product of trimethylolpropane and
ethylene oxide having an OH number of 165 and
4.00 g dibutyltin dilaurate
______________________________________
were added. The mixture was heated rapidly to 120.degree. C. under a gentle
stream of nitrogen. Subsequently, over the course of 6 hours, the
temperature was raised gradually to 190.degree. C. and the water of
condensation produced was removed by distillation, to give a soft resin
having an acid number of 31.
Comparison Example
______________________________________
490.30 g maleic anhydride (5.0 mol)
______________________________________
were weighed into a stirring flask fitted with heater and distillation
device and were heated to 100.degree. C. under a gentle stream of
nitrogen. Then
______________________________________
775.20 g 1,3-phenoxypropanol (5.1 mol)
______________________________________
were added from a dropping funnel over the course of one hour, during which
a slightly exothermic reaction took place. The mixture was left to
after-react at 125.degree. C. for one hour. The monoester of
maleic/fumaric acid with 1,3-phenoxypropanol was formed, which contains no
readily abstractable hydrogens. The contents of the flask were cooled to
70.degree. C. and then
______________________________________
1730.00 g ethoxylation product of trimethylolpropane and
ethylene oxide having an OH number of 165
4.00 g dibutyltin dilaurate and
4.00 g hydroquinone
______________________________________
were added. The mixture was heated rapidly to 120.degree. C. under a gentle
stream of nitrogen. Subsequently, over the course of 6 hours, the
temperature was raised gradually to 190.degree. C. and the water of
condensation produced was removed by distillation, to give a liquid of
medium viscosity having an acid number of 18.
Curability Testing of the Products of the Above Examples and in the
Comparison Example
The compounds of Examples 1 to 3 and the Comparison Example were used, for
greater ease of handling, as 80% solutions in methyl ethyl ketone. 4% of
t-butyl perbenzoate and 3% of benzophenone, based on the total quantity of
dissolved substances, were added to the solutions.
The solutions were knife-coated onto steel panels in a coat thickness of
about 80 .mu.m. The solvent was removed from the films at 40.degree. C.
under reduced pressure over the course of 3 hours, giving tack-free films.
The films were first of all irradiated with a medium-pressure mercury lamp
at an energy level of 80 mW/cm.sup.2 for 240 seconds. In the case of
Examples 1 to 3, this gave a tack-free skin beneath which there were still
tacky constituents; the tack of the Comparison Example product was
unchanged. The panels were then baked in an oven at 180.degree. C. for 30
minutes. After cooling, hard, ethanol-resistant films with good flexural
strength were obtained in the case of Examples 1 to 3; even after baking
there was virtually no reduction in the tack of the Comparison Example
product.
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